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1. DETAILS MY NOTES ASK YOUR TEACHER A hanging weight, with a mass of my = 0.360 kg, is attached by a cord to a block with mass m2 = 0.810 kg as shown in the figure below. The cord goes over a pulley with a mass of M = 0.350 kg. The pulley can be modeled as a hollow cylinder with an inner radius of R, = 0.0200 m, and an outer radius of R2 = 0.0300 m; the mass of the spokes is negligible. As the weight falls, the block slides on the table, and the coefficient kinetic friction between the block and the table is MK = 0.250. At the instant shown, the block is moving with a velocity of v; = 0.820 m/s toward the pulley. Assume that the pulley is free to spin without friction, that the cord does not stretch and does not slip on the pulley, and that the mass of the cord is negligible. R mg (a) Using energy methods, find the speed of the block (in m/s) after it has moved a distance of 0.700 m away from the initial position shown. 2.05 x m/s (b) What is the angular speed of the pulley (in rad/s) after the block has moved this distance? 68.33 X rad/s Submit Answer 2. DETAILS MY NOTES ASK YOUR TEACHER An electric motor rotating a workshop grinding wheel at 1.20 x 102 rev/min is switched off. Assume the wheel has a constant negative angular acceleration of magnitude 1.92 rad/s2. (a) How long does it take the grinding wheel to stop? 5.56 XS (b) Through how many radians has the wheel turned during the time interval found in part (a)? 1.45 X rad